1. Field of the Invention
This invention relates to the flow of pellets which may simulate snow and more particularly to an apparatus and method for effecting and controlling such flow.
2. Description of the Related Art
Prior art devices and methods are known for effecting the flow of pellets which may simulate snow. Such devices are often utilized to simulate the flowing of snow on a Christmas tree and generally employ a blower which blows the pellets into a venturi tube through which such particles are drawn through a tube to the top of the tree and then dispensed. When the particles reach the bottom of the tree, they are recirculated to the top. Such prior art devices are described in U.S. Pat. No. 5,412,888 issued May 9, 1995 to Rickuss et al.; U.S. Pat. No. 5,200,239 issued Apr. 6, 1993 to Chen; and U.S. Pat. No. 4,962,922 issued Oct. 16, 1990 to Chu. In none of these prior art devices is there any mechanism for changing the venturi action to enable variations in the fluid pressure and simultaneously changing the rate of flow of pellets. Without such an adjustment, neither the rate or velocity of the flow can be controlled which could result in overflow leading to blockage of the tube thereby terminating the flow of pellets. Further, to produce different effects, in certain situations a greater flow volume or velocity of flow is desired and in others a lesser flow and velocity of flow is needed. Also, the flow volume and velocity of flow may be governed by the size of the pellets.
The device and method of the present invention by enabling control of the volume and velocity of flow of the pellets as pointed out above, provides distinct advantages over the prior art.
The system of the present invention includes a venturi tube which is part of a flow channel from a supply position to a dispensing position generally above the supply position. Pellets stored in a container member are sucked into the venturi tube and from there are fed to one end of an elongated tube. The pellets are driven by the air pressure to the opposite end of the tube where they are dispensed to fall downwardly onto an object such as a Christmas tree. The particles fall through the object and are collected in the container member for recycling. An adjustable flap member is formed in the venturi tube, the opening provided by this flap member valve being manually adjustable to vary the size of the opening in the venturi tube. In this manner, the venturi action of the venturi tube is set to determine the pressure differential between the input and output of the venturi tube with the position of the flap simultaneously determining the rate of flow of pellets through the venturi tube.
It is therefore an object of this invention to provide an improved system and method for dispensing pellets;
It is a further object of this invention to provide a system and method for dispensing pellets in which the rate of flow of the pellets and the air pressure driving such flow can be simultaneously controlled;
It is a still further object of this invention to provide a system and method utilizing a venturi tube for dispensing pellets at a predesired velocity and volume to simulate snowfall on a tree.
Other objects of the invention will become apparent from the following description in conjunction with the accompanying drawings.